In 1987 an entomologist with the Natural History Survey named Eli Levine got a call from a Piper City grain-elevator agronomist who was seeing damage in corn that had been rotated with soy. (Draped over his desk chair is a T-shirt he made: two mating rootworms and the caption, “We like to watch.”) His colleagues there call him “Cornboy,” and although Spencer turned 53 last October, there is indeed something boyish about him, from his Dennis the Menace grin to his impish enthusiasm for all things corn and rootworm. Spencer's office at the Illinois Natural History Survey is littered with corn paraphernalia: corn-themed signs, mugs, bottles and silverware he picked up from eBay. “You can only slow it down.” Behavior Change And scientists and farmers alike know it is only a matter of time until the rootworm evolves to resist the new corn.“You can't stop resistance,” Spencer says. But environmentalists are concerned gene alterations may harm helpful insects such as ladybugs. The new technology should arrive in fields by the end of this decade. Today farmers and scientists are pinning their hopes on a new modification-a corn laced with special genetic molecules that work within a rootworm cell nucleus to shut down crucial genes. But Spencer saw in Wyllie's fields that rootworms were winning.
For the past decade the weapon of choice has been famously controversial genetically modified corn plants that make chemicals to kill rootworm larvae. And then, “just in time, the good guys in the white hats ride into town,” Spencer says, with a new beetle-killing weapon. The result is an evolutionary arms race: the beetle damages farmers' crops seed companies create a product to kill it the beetle evolves to resist the product the corn gets infested again. Agriculture companies spend hundreds of millions developing products to help them do so. Farmers spend hundreds of millions in chemicals, seeds and labor fighting it. The crop brings in $50 billion in annual sales. It frequently covers 80 million acres and sometimes more. The beetle spends its life cycle on corn, and corn is the nation's largest crop by far.
It is known as the “billion-dollar bug”-although in fact it probably costs the U.S. The rootworm- Diabrotica virgifera virgifera-is the most expensive and consequential pest in American agriculture. And he knew that the insects swirling around him meant trouble not only for Wyllie's crop but for the entire Midwestern corn belt. The worst-case scenario.’” Spencer has spent most of his career studying rootworm behavior at the Illinois Natural History Survey at the University of Illinois at Urbana-Champaign. “I got a chill down my back,” Spencer remembers. But in the field that day, Spencer could see that these approaches-the most successful and widely used strategies to fight the pest-had failed. He planted corn seeds that were genetically engineered to release a toxic protein that kills the hungry larvae. He rotated his corn crop with soy every other year to interrupt the rootworm food supply. Wyllie, who farms 1,000 acres, told Spencer he had done everything the experts recommended to fight the insects. The beetles are Western corn rootworms, and it had been their wormlike larvae that gnawed Wyllie's corn roots to destruction. Spencer had to close his mouth to keep the insects out. They clambered on leaves, mating, defecating and munching on corn silk. And the air was teeming with grain-sized, yellow-and-black striped beetles. Some plants had tipped over from their own weight. Spencer could pull one from the ground with a flick of his wrist the once white roots underneath were gnawed and brown, like teeth gone rotten. The stalks had twisted back on themselves like the neck of a goose. Wyllie's corn, however, had developed a personality. In good growing years, crop corn around Piper City and elsewhere is as standardized and predictable as a widget rolling off an assembly line: the plants have the same spacing, the same height. Spencer, an entomologist who studies farm insects, was looking for a farmer named Scott Wyllie. In late August of 2013, a man named Joseph Spencer followed a corn-flanked county road northwest from Piper City until his GPS advised him to leave the road altogether and turn onto a gravel track. It is a farm town with a skyline of grain elevators, a tidy grid of pitch-roofed houses and, a few blocks beyond, endless fields: corn, soybean, corn, soybean, corn, corn, corn, perfectly level, perfectly square, no trees, no cows, no hedgerows, no bare land. There is, despite the name, nothing urban about Piper City, Ill.
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